I have a battery powered Arduino project that need to be very low power and wake up and run once a day once it’s getting dark or is dark outside. My thought was to use a resistor divider with a photocell to pull a pin up down which would interrupt wake the Arduino and have it run its routine. However, once it's dark and the Arduino wakes up to run its routine, I want it to go back to sleep until it’s dark again the next night. Is it possible to set the interrupt change from waking when it goes low to waking when it goes high once the program is running?
If so, then I could write a program that wakes the Aruindo when it’s dark out, runs it's routine, then changes the interrupt to look for when it’s light out and put it to sleep. When it wakes up when it’s light out I can tell it to change the interrupt again to look for when it’s dark out again and that will get me to keep the arduino sleeping but wake and run my routing the next night. Am I overthinking this and should I just use a timer to get the Arduino to sleep at low power for 12 hours until it's light again and then look for a darkness interrupt after the 12 hours is up or is there a better way to do this?